{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-126300","assignerOrgId":"83251b91-4cc7-4094-a5c7-464a1b83ea10","state":"PUBLISHED","assignerShortName":"VulnCheck","dateReserved":"2026-11-10T20:15:54.612Z","datePublished":"2026-11-13T09:36:25.918Z","dateUpdated":"2026-11-13T09:36:25.918Z"},"containers":{"cna":{"providerMetadata":{"orgId":"83251b91-4cc7-4094-a5c7-464a1b83ea10","shortName":"VulnCheck","dateUpdated":"2026-11-13T09:36:25.918Z"},"datePublic":"2026-10-26T00:00:00.000Z","title":"NLTK from 3.2.5 before 3.10.4 CPU Exhaustion via TreebankWordTokenizer.span_tokenize","descriptions":[{"lang":"en","value":"NLTK from 3.2.5 before 3.10.4 contains an algorithmic complexity vulnerability in TreebankWordTokenizer.span_tokenize that allows remote attackers to cause quadratic CPU consumption through repeated list.pop(0) calls. Attackers can submit long runs of double-quote characters to services span-tokenizing untrusted text, exhausting a CPU core and degrading availability."}],"problemTypes":[{"descriptions":[{"lang":"en","description":"Inefficient Algorithmic Complexity","cweId":"CWE-407","type":"CWE"}]}],"affected":[{"vendor":"nltk","product":"nltk","defaultStatus":"unaffected","packageURL":"pkg:pypi/nltk","versions":[{"version":"3.2.5","status":"affected","versionType":"semver","lessThan":"3.10.4"},{"version":"3.10.4","status":"unaffected","versionType":"semver"}]}],"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:a:nltk:nltk:*:*:*:*:*:*:*:*","versionStartIncluding":"3.2.5","versionEndExcluding":"3.10.4"}]}]}],"metrics":[{"format":"CVSS","cvssV4_0":{"version":"4.0","vectorString":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N","attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"NONE","privilegesRequired":"NONE","userInteraction":"NONE","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"NONE","vulnAvailabilityImpact":"LOW","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","subAvailabilityImpact":"NONE","baseScore":6.9,"baseSeverity":"MEDIUM"}},{"format":"CVSS","cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"LOW","baseScore":5.3,"baseSeverity":"MEDIUM"}}],"references":[{"url":"https://github.com/nltk/nltk/security/advisories/GHSA-ffr9-mgrr-wcvr","tags":["vendor-advisory"],"name":"GitHub Security Advisory (GHSA-ffr9-mgrr-wcvr)"},{"name":"VulnCheck Advisory: NLTK from 3.2.5 before 3.10.4 CPU Exhaustion via TreebankWordTokenizer.span_tokenize","tags":["third-party-advisory"],"url":"https://www.vulncheck.com/advisories/nltk-from-3.2.5-before-3.10.4-cpu-exhaustion-via-treebankwordtokenizer-span-tokenize"}],"credits":[{"lang":"en","value":"manus-pi","type":"reporter"},{"lang":"en","value":"manus-use","type":"reporter"}],"x_generator":{"engine":"vulncheck-endgame"}}}}